Module Name: src
Committed By: riastradh
Date: Sat Apr 16 18:28:22 UTC 2016
Modified Files:
src: UPDATING
Log Message:
Add a note about PIE for amd64 requiring clean objdir.
To generate a diff of this commit:
cvs rdiff -u -r1.267 -r1.268 src/UPDATING
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/UPDATING
diff -u src/UPDATING:1.267 src/UPDATING:1.268
--- src/UPDATING:1.267 Sun Apr 3 06:16:02 2016
+++ src/UPDATING Sat Apr 16 18:28:22 2016
@@ -1,4 +1,4 @@
-$NetBSD: UPDATING,v 1.267 2016/04/03 06:16:02 mrg Exp $
+$NetBSD: UPDATING,v 1.268 2016/04/16 18:28:22 riastradh Exp $
This file (UPDATING) is intended to be a brief reference to recent
changes that might cause problems in the build process, and a guide for
@@ -19,6 +19,25 @@ See also: BUILDING, build.sh, Makefile.
Recent changes:
^^^^^^^^^^^^^^^
+20160410:
+
+ amd64 needs full "make cleandir" or deletion of objdir now that
+ PIE has been enabled for amd64. PIE, or position-independent
+ executables, means all code, including executables and not just
+ shared libraries, is position-independent and hence able to be
+ relocated by ASLR, address space layout randomization.
+
+ The change was made in Makefile variables for compiler and
+ linker flags, for which make(1) does not record dependencies,
+ hence it is unable to detect that all .o files need rebuilding.
+
+ Partial rebuilds with some modified source files will likely
+ fail when linking executables, since the linker refuses to mix
+ position-independent code with position-dependent code in
+ position-independent executables:
+
+ .../x86_64--netbsd/bin/ld: foo.o: relocation R_X86_64_32 against `...' cannot be used when making a shared object; recompile with -fPIC
+
20160401:
Ports switching to GCC 5.3 will need a full "make cleandir".
